Tuesday, May 15, 2018

The Start of Ramadan - Legal Opinions and Community Cohesion


For many Muslims, the determination of the Islamic calendar can be a source of confusion—and often, such as when there are multiple dates for the beginning of Ramaḍān or for the two ʿĪds, it can be a cause of considerable frustration as well.
The article below was originally written some years ago to shed light on the operation of the Islamic calendar and answer common questions that arise when various individuals and organizations reach different conclusions about the start of the month. We are publishing it in an updated version in this issue of al-Sidrah before the start of the blessed month of Ramaḍān.
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Questions about the calendar and the importance of sighting the crescent moon are not exclusive to the modern era. As the Qurʾān tells us, such questions existed in the time of the Prophet (s) himself.
We read in Sūrat al-Baqarah of the Qurʾān:
They ask you about the crescents. Say: They are times appointed for the people and for the hajj… (al-Qurʾān, 2:189)
This verse sets the new crescent as the standard for the beginning of the Islamic month. In this way, Islam introduced a purely lunar calendar that was distinct from the different calendars in use at the time in Arabia and elsewhere. Along with verses 36 and 37 of Sūrat al-Tawbah, which prohibit any form of modification or tampering with the calendar, this verse introduced a uniquely observational calendar that was directly accessible to the people without making them dependent on calculations, astrologers, or any central coercive authority.
By establishing such a standard, Islam empowered the people: unlike other religions and civilizations, no emperor, priest, or king could impose his authority upon them by controlling or abusing the religious calendar. At the same time, a corresponding responsibility was placed on the people’s shoulders: to determine each new month, they would have to learn to communicate with each other effectively and negotiate differences of opinion and understanding that naturally arise in any area of human endeavor.
For the Islamic calendar to fulfill its proper and intended function in society and in order to avoid doubt, confusion, and disunity, Muslims need to have some familiarity with the legal criteria for determining the beginning of the month.  The first question which generally arises is, “Why can’t Muslims achieve unity on such an important issue in the first place?”

The Role of Ijtihād

To answer that question, it is important to understand the nature and importance of the process of ijtihād—the process of deriving religious laws from the Qurʾān and Sunnah—within Islam, especially in the school of Ahl al-Bayt (a). When there are different fatāwā (pl. of fatwā) or religious rulings about an issue, it is common for people to ask questions along the lines of, “Why don’t the scholars just get together, solve the issue, and give a single answer?”
This question reflects the natural tension that exists between free scholarly debate and uniformity of action.  In any field of human endeavor, there is a tradeoff that arises in allowing academic disagreement: it permits scholarship to progress and develop, but it also leads to less conformity and agreement in practice. Two doctors may reach different conclusions about the best way to treat an illness; economists may offer different models and suggestions to prevent a recession; and jurists may differ in their interpretation of secular or religious law. On the other hand, imposing a specific solution or answer to a problem prevents confusion and disunity in practice, but it stifles the advancement of knowledge.
Within the Sunni world, the introduction of the four well-known schools of fiqhḤanafīMālikīShāfiʿī, and Ḥanbalī—was just such an attempt to impose conformity on people’s religious practice by the Abbasid government of the time, who feared the proliferation of ever-increasing schools of fiqh among Muslims. By limiting the acceptable legal schools to four, they hoped to keep differences of opinion and practice within a manageable level.
However, within the school of Ahl al-Bayt (a) the practice of ijtihād has remained a continuous and unencumbered process from the time of the Imāms until the present day. The minor differences in religious rulings that do sometimes result are far outweighed by the benefits of the dynamic process of religious scholarship.

The Role of Taqlīd in Religious Practice

It is a misconception that taqlīd means following a faqīh (Islamic jurist) in all matters pertaining to religious practice.  In reality, there is a difference between the legal ruling and its application. Taqlīd means abiding by the religious verdicts and rulings of a faqīh; these rulings are commonly known as fatwā (pl. fatāwā) in Arabic. However, the application of those rulings in daily life depends on determining that the conditions to which a particular ruling applies actually exist, and that is neither the role of a faqīh, nor necessarily his area of expertise.
For example, the faqīh will give us the ruling that wine is najis and ḥarām to ingest, and he will explain the standard by which to determine what constitutes wine. That standard—his religious ruling—is binding on those who follow him. But if we take a particular liquid to him and ask, “Is this wine?” the answer is not binding. Even if he says with certainty that it is wine, if we know he is wrong or even if we are uncertain, we are no more bound by his pronouncement than that of someone else. Instead, we have to refer to our own certainty or to experts who can make that determination. The faqīh himself may or may not be such an expert with regard to a particular subject.
The moon sighting is one such issue where some people assume they should simply follow their faqīh in his declaration, but like the example given above, that is not what taqlīdentails. One refers to the faqīh to determine what standard to apply in starting the new Islamic month, but actually applying the standard is not subject to taqīid.

Declaration of the First of the Month by a Faqīh

Although the start of the Islamic month is not subject to taqlīd, there are some jurists who say that a faqīh can make a ruling declaring the beginning of the month. This is known as a ḥukm and not a fatwā, because it too has nothing to do with taqlīd. For the followers of jurists who consider such a declaration valid, it is binding if it is made by any faqīh—not only the faqīh whom that person follows in taqlīd.
To illustrate this point, let us look at the rulings of some of our present-day jurists. Sayyid Sistani holds that the faqīh does not have the prerogative of declaring the start of a new month, and such a declaration is not binding on others, though it is recommended to observe precaution (for example, by fasting without the intention of Ramaḍān):
The 1st day of any month will not be proved by the verdict of a Mujtahid and it is better to observe precaution.[1]
In contrast, both Sayyid Khamenei and Shaykh Makarim Shirazi consider the ruling of a jurist to be authoritative. In his answers to legal queries, Sayyid Khamenei states:
… and similarly if a religious jurist rules about the crescent, his judgment will be a religious hujjah (authority) for all believers, and it is obligatory on them to obey it.[2]
It should be noted that this only applies if the religious authority actually issues a ruling regarding the beginning of the month. If however, he is personally convinced about the moon sighting without issuing a ruling to that effect, that does not mean others are required to follow the same dates as he is following:
Until a religious authority issues a decree announcing the sighting of the new crescent, the mere ascertaining of it by him is not sufficient for others to follow him, unless they are convinced thereby of the end of Ramaḍān.[3]
In addition, even the ruling of a religious authority will not be binding on those who, through whatever means, know that ruling to have been made in error.[4]
Thus, for followers of Sayyid Sistani, they cannot follow the statement of either their own faqīh or any other jurist unless they are personally satisfied that it is correct (or, of course, if the crescent has been established by other means.)
Followers of Sayyid Khamenei or Shaykh Makarim, however, would have to follow the declaration of a religious authority, even if that declaration was not made by the jurist they follow in taqlīd. So a ruling by Sayyid Khamenei would be binding on followers of Shaykh Makarim as well.

Criterion for the Start of the Month

There is a near consensus among Shīʿī jurists that the criterion for the start of the Islamic month is for the new crescent to be visible in the sky; most jurists specify that it must be visible to the unaided eye (and not through a telescope or other instrument). The visible crescent is not the same as the new moon, which is actually invisible from earth. The crescent usually becomes visible one or two days after the new moon. Unlike the new moon, the visibility of the crescent cannot be calculated or predicted with absolute certainty.

Using Astronomy to Determine the Start of the Month

There is also consensus among jurists that using astronomy or calculations to determine the new month is not allowed, unless one derives certainty through those means. In that case, it is permitted.[5]
There is a common misconception that astronomy gives definitive answers and should be able to resolve any disputes about the beginning of the Islamic month. In reality, the visibility of the crescent is different from calculations of sunrise, sunset, the new moon, and so forth—all of which can be calculated with precision.
The visibility of the new crescent depends on many different factors, including the age of the moon, its angular separation from the sun (which affects how much of the moon’s surface is illuminated), and when the moon sets. Experts have created models based on these and other factors that in some instances can rule out the moon’s visibility and in other instances can say with certainty that the moon will be visible, but this is not true in all cases.
Thus, even though it cannot be relied on in entirety, there is a clear role for astronomy in moon sighting, especially in ruling out reports or claims of seeing the crescent where such a sighting was not actually possible.[6]

Eyewitness Testimony of the Moon sighting

There are several ways to establish the new crescent. Whether a jurist’s declaration is binding or not was discussed above. The other ways are:
  1. for a person to see the crescent personally,
  2.  for its sighting to have been established with certainty (for example if a large number of men and women saw the moon),
  3. for thirty days to have passed from the start of the previous month,
  4. or for two ʿādil witnesses to testify that they have seen the crescent.
With regard to the testimony of two ʿādil witnesses, there are two opinions among Shīʿī jurists. One holds that their testimony is valid as long as:
  1. they do not contradict one another[7]
  2. they are not contradicted by at least two other ʿādil witnesses who say the crescent moon was not visible[8]
  3. a person does not have personal certainty that they are in error.[9]
  4. Sayyid Khamenei and Shaykh Makarim Shirazi hold this view.[10]
Sayyid Sistani, however, expresses the conditions for the testimony of witnesses to be admissible differently:
If two just (Adil) persons say that they have sighted the moon at night. The first day of the month will not be established if they differ about the details of the new moon. This difference can be either explicit or even implied.
For example, when a group of people goes out in search of a new moon and none but two Adils claim to have seen the new moon, though, among those who did not see, there were other Adils equally capable and knowledgeable [in terms of locating the crescent], then the testimony by the first two Adils will not prove the advent of a new month.[11]
Thus, in the view of Sayyid Sistani, the sighting of the moon should be something that is clearly and unambiguously established. If the crescent is visible in the sky and many people go out to look for it, it does not make sense for many or most of them not to see it. In several questions that were asked of him, Sayyid Sistani has specified that this standard applies even if the reported sightings of the crescent were more than two in number:
لو كان هناك اكثر من شاهدین عادلین بالرؤیة (اربعة او ستة او ثمانیة شهود بالرؤیة) فهل هذا یعني وقوعهم بالخطأ والاشتباه علیه تترك شهادتهم؟
الجواب: یمكن الخطأ في العشرة ایضا.
This was part of a question regarding a case in which more than two ʿādil witnesses report seeing the moon even though it is not astronomically possible:
What if there are more than two ʿādil witnesses to the sighting (four, six, or eight witnesses to the sighting)?  Does this mean that they are in error and their testimony will be rejected?
Answer: Even ten people can be in error [let alone a smaller number].
Another question and answer deal specifically with the issue of a crescent that was seen by some people but not others:
في بعض الشهور يعلن عن ثبوت الهلال عند بعض العلماء في بعض بلاد الشرق استناداً الى أقوال بعض من شهدوا برؤيته فيها، ولكن يقترن ذلك ببعض الأمور:
أـ كون الشهود وعددهم 30 مثلا ـ موزعين على عدة بلدان، مثلا (2) في أصفهان، (3) في قم، (2) في يزد، (4) في الكويت، (5) في البحرين، (2) في الأحساء، (6) في سوريا، وهكذا.
ب ـ صفاء الافق في عدد من البلاد الغربية واستهلال المؤمنين فيها مع عدم وجود مانع لرؤية.
ج ـ اعلان المرصد الفلكي البريطاني انه يستحيل رؤية الهلال في تلك الليلة في بريطانيا ما لم يستخدم المنظار)التلسكوب( وأن رؤيته بالعين المجردة إنما يتيسر في الليلة اللاحقة.
فما هو الحكم في هذه الحالة؟ افتونا مأجورين.
الجواب: إنّ العبرة باطمئنان المكلف نفسه بتحقق الرؤية أو بقيام البينة عليها من دون معارض، وفي الحالة المذكورة ونظائرها لا يحصل عادة الاطمئان بظهور الهلال على الأفق بنحو قابل للرؤية بالعين المجردة، بل ربما يحصل الإطمئنان بعدمه وكون الشهادات الصادرة مبنية على الوهم والخطأ في الحس، والله العالم.
During certain months, it is declared that the sighting has been proven according to some religious scholars in some eastern countries. This is based on the testimony of those who have sighted the new moon. Such declarations are usually coupled with the following facts:
  1. The witnesses who sighted the moon and who number around thirty, for example, are scattered in various cities such as 2 in Isfahan, 3 in Qum, 2 in Yazd, 4 in Kuwait, 5 in Bahrain, 2 in Aḥsāʾ, and 6 in Syria, etc.
  2. The sky was clear in a number of cities in the West, and the believers went out in the attempt to sight the moon; and there was nothing preventing the sighting.
  3. The observatories in England announced that it was impossible to sight the new moon that evening in England except by using a telescope; and that its sighting with the naked eye would be possible only in the following night. So, what is the ruling in such a case? Please guide us, may Allāh reward you.
Answer: The criterion is the satisfaction of the individual himself [1] about the actual sighting [of the new moon] or [2] the proof of sighting without any counter claim. In the case mentioned above, satisfaction is not normally achieved concerning the appearance of the new moon on the horizon in such a way that it could have been sighted by the naked eye. On the contrary, one is satisfied that it was not sighted and that the testimony [of sightings in the Eastern cities] is based on illusion and error in sight. And Allāh knows the best.[12]
In short, the beginning of each Islamic month must be based on certainty, and even the testimony of trustworthy and ʿādil witnesses cannot be utilized unless it fulfills the standard mentioned above.

Evaluating Sighting Reports Scientifically

As mentioned earlier, astronomical models are still not precise enough to tell us with absolute certainty exactly where the crescent will or will not be visible in all cases. This is because of the many factors, both astronomical and atmospheric, that affect its visibility.
At the same time, it is frequently possible to scientifically rule out the prospect of sighting in a particular area, a fact which we can also see reflected in the questions posed to Sayyid Sistani that are quoted above. Experts have created astronomical models that explain the possibility of seeing the crescent in terms of “visibility curves” that spread westward across the globe. These curves, plotted on a map or globe, show where the crescent should be visible with ease, where it may be visible under perfect atmospheric conditions, where optical aids may be needed to find or see it, and finally, where the crescent will not be visible at all, even with telescopes.
The models created in this way are based on astronomical realities and are corroborated by years, or even centuries, of observations, and thus are extremely reliable—especially in ruling out any report of sighting the crescent that originates from outside of even the widest visibility curve (in which the crescent can only be seen with optical aid, not with the naked eye). So if there is a case where a reported sighting conflicts with conclusive astronomical data, it can be discounted.

Reported Sightings and Astronomical Models

One might be tempted to say that if the moon sighting is reported by trustworthy and ʿādilwitnesses even though the astronomical models show it to be impossible, that should call into question the validity of those models rather than result in the discounting of the witnesses’ testimony.
To understand why that is not necessarily the case, it is important to understand that it is entirely possible and even common for people to think they have seen the moon when in reality they have not. Clouds, dust, pollution, and other natural factors can sometimes be confused for the young crescent. And of course, today there are also many manmade objects in the sky that can confuse even an experienced observer, such as aircraft and various types of satellites. This type of confusion existed even in the era of the Imāms, as evidenced by this ḥadīth from Imām Ṣādiq (a), in which he was asked how many witnesses are sufficient in sighting the crescent.  The Imām replied:
إن شهر رمضان فريضة من فرائض الله، فلا تؤدوا بالتظني.  وليس رؤية الهلال أن يقوم عدة فيقول واحد: قد رأيته، ويقول الآخرون: لم نره؛ إذا رآه واحد رآه مائة، وإذا رآه مائة رآه ألف.  ولا يجزئ في رؤية الهلال إذا لم يكن في السماء علة أقل من شهادة خمسين، وإذا كانت في السماء علة قبلت شهادة رجلين يدخلان ويخرجان من مصر.
Verily, the month of Ramaḍān is one of the Divine obligations, so don’t base it on conjecture. And sighting the crescent is not for a group to go out, and then one says, “I have seen it,” while the others say “We didn’t see it.” If one sees it, a hundred see it, and if a hundred see it, a thousand see it. And in sighting the moon, the testimony of less than fifty is not sufficient if there is no obstacle in the sky; and if there is an obstacle, the testimony of two men who enter and leave a city is acceptable.[13]
There are several other similar aḥadīth from the Imāms that demonstrate that mistaken sightings were an issue even in that era, before pollution and the presence of foreign objects in the sky were as much of an issue as they are today.
Thus, if the astronomical models and data are conclusive in eliminating the possibility of sighting, that determination in fact can be relied upon even if there are reports of the moon sighting. However, if the scientific models are not conclusive, the eyewitness testimony cannot be discounted.


It sometimes happens that various Shīʿī and Sunnī centers arrive at different dates for the start of the Islamic month. In accordance with the different scholarly opinions, some rely on reported sightings, while others make use of astronomical models and calculations. Whatever determination an individual may make, it is important to bear in mind that unity does not require conformity, but rather respect and understanding for those who may have come to a different determination.

[1] Islamic Laws, Issue 1740.  See also المسائل المنتخبة، المسألة 475.
[2] “وهكذا لو حكم الحاكم الشرعي بالهلال كان حكمه حجة شرعية لعامة المكلفين ووجب عليهم اتباعه.”
[3] Practical Laws of Islam, Question 839.
[4] Tawḍīh al-Masāʾil, Shaykh Makarim Shirazi, Issue 1456.
[5] Tawḍīh al-Masāʾil, Shaykh Makarim Shirazi, Issue 1457. See also Islamic Laws, Sayyid Sistani, Issue 1741.
[6] “On the Crescent’s Visibility,” S. Kamal Abdali, Ph.D. (http://patriot.net/~abdali/ftp/moon.pdf)
[7] For example, if one says the moon was in one direction and the other says it was in another direction, their testimony will not be valid.
[8] In this case, if two ʿādil witnesses say, “We saw the crescent,” and two others say, “We did not see it,” the testimony of the first group will be admissible. But if the second group actually denies and the sighting of the crescent itself, for example, by saying, “We looked, and the crescent wasn’t there,” then the two conflicting testimonies cancel each other and neither is admissible.
[9] For example, if two ʿādil witnesses testify to seeing the moon but a person is satisfied by scientific or other means that their sighting is mistaken or in error.
[10] Practical Laws of Islam, Issue 837; Tawḍīh al-Masāʾil, Issue 1456. Shaykh Makarim adds that if the two witnesses mention attributes of the crescent that indicate they made a mistake, their testimony does not prove the new month—even if they don’t contradict one another.
[11] Islamic Laws, Issue 1739.
[13] Wasāʾil al-Shīʿah, vol. 10, p. 289

Moon Sighting fiqh short video series

The YouTube links are gone but I did find this:


Saturday, May 27, 2017

Maher Zain Ramadan

The name 'Ramadan'

The name 'Ramadan' is derived from an Arabic word associated with burning.  In the process of intense and devoted prayer and fasting, the devotee burns away the energies of worldly concerns and then trusts God to reconstruct energies of reverence for Him and obedience to His will.  Fearing God is to acknowledge His awesome power and to realize the importance of living in complete submission to Him.  Ramadan gives the devotee the opportunity to burn vain energies and to change their composition into self-discipline and divine awareness so that the devotee may attain spiritual success.

-Linda Barto in Ramadan Rhapsody

Sunday, May 7, 2017

Why we Fast - by Amanda Quraishi

– Fasting Is Supposed to Suck; That’s Why We Do It

By Amanda Quraishi
I performed my first Ramadan fast when I was 25 years old. I’d embraced Islam, spoke the words of the Shahada and learned my prayers with enthusiasm; but as the holy month drew closer on the calendar, I prepared for it with trepidation. Fasting for 30 days, even with the allowances of eating and drinking during the nighttime hours, was a daunting endeavor.
That first year I lasted for about a week and then gave up the fast in total dismay. It seemed impossible. I live in a country where the majority of people around me are not fasting.  Our work schedules don’t change just because it’s Ramadan. We’re required to stay as sharp and focused as our not-Muslim co-workers during the day. We also do our own domestic chores. Cooking, cleaning and laundry don’t go away just because it’s Ramadan. The discomfort and exhaustion I experienced during those first fasts was completely opposite from the spiritual high I was hoping to achieve during this holiest of months.
Yet, I would look around at other Muslims and see that they were successfully fasting while maintaining a positive attitude.  Rather than inspiring me, seeing other Muslims with a “Ramadan Glow” made me mad. I resented people who seemed to truly be enjoying the experience while I struggled and failed again and again to keep the daily fasts because of hunger, thirst, headaches and exhaustion. Surely they must be faking it, I thought.
Aside from the logistical issues of Ramadan in the U.S., fasting is, in every sense, a spiritual discipline that requires all the things I struggle with: patience, consistency, focus and self-control. Still, in spite of the challenges Ramadan presents, each year for the past 14 years I have made preparations, set my intentions and began the fast, praying that it be pleasing to Allah (SWT).
About three years ago, however, I had a Ramadan Breakthrough. It was a simple revelation that suddenly brought everything into perspective.  You see, fasting sucks.  And it sucks on purpose. It’s supposed to be a challenge. That’s why we do it! I realized that the joy that many of my Muslim friends were experiencing from fasting was like that of a marathon runner who, despite the physical discomfort she experiences, stays bolstered with every mile she completes on the course. As she nears the finish line and her dedication and perseverance pays off it makes the aches and pains, blisters and exhaustion all seem worth it.
If you look at it objectively, it seems almost insane that a person would get up out of bed on a Saturday morning and attempt to run 26 miles; continuing to run even when she is exhausted, near dehydration and in pain. Not-Muslim friends and family often look at our Ramadan fast the same way. Why would you subject yourself to that kind of torture? But any runner will tell you that there is no feeling like crossing the finish line, and any faster will tell you there’s nothing more satisfying than that first sip of water and a date after a long day of abstinence.
These disciplines –physical, mental and spiritual — that we humans engage in cause us to transcend our comfort and, sometimes, even logic. We do these things precisely because they force us out of our comfort zones and challenge us in ways that we inherently understand are important; especially in a culture like that of the U.S., where we are constantly seeking new ways to be comfortable. Every new product or service promises to make our lives easier, more fun and help us feel better.
When we intentionally make our lives harder and allow ourselves to experience discomfort, we gain valuable perspectives and allow our mettle to be tested. The reward is the confirmation that we have the ability to overcome our own weaknesses, which is even more satisfying in the case of Ramadan when we’re doing it for the glory of the One God.
These days, I look forward to Ramadan. I’ve also become a runner. I don’t think these two things have happened coincidentally. They are both a sign that I’ve matured and have learned to appreciate the purpose of self-discipline in different areas of my life.
When I first started running, a friend of mine offered me a great piece of advice. He said, “It’s your race, your pace. Running is a competition against yourself. Pay attention to your unique needs, understand what your body requires to meet your goal, and forget about anyone else.”
Every year, millions of marathon runners sign up to run in races that they know they won’t ‘win.’  Sure, there are a handful of elite runners who are there to try to be first across the finish line, but most marathon runners aren’t competing against anyone but themselves and their last race time. The goal is to simply finish the course and do better than you’ve done before.
In the same way, fasting is not a competition between you and anyone else. It’s a struggle against your own nafs, a challenge that you must meet on your own. Sure, you can ask other Muslims for advice on fasting, but find the way that works best for you. Maybe you need to do unconventional things to be able to manage your schedule or juggle your responsibilities during Ramadan. As long as you are sticking to the basic requirements of the fast, that’s ok. If you fail, just get up the next day and start again.
Islam is not a destination. It’s a path — a ‘straight path’ that requires a lifetime of perseverance and dedication. Ramadan is a blessed part of that journey, and the only way you can ever really “lose” at it is to just stop trying.
Amanda Quraishi is a writer, interfaith activist and technology professional living in Austin, Texas.  She currently works full time for Mobile Loaves & Fishes, a non-profit organization that addresses the issue of homelessness in the U.S.  She also leads a populist-based interfaith initiative at InterfaithActivism.org, and blogs about the American Muslim experience at muslimahMERICAN.com.

Thursday, June 9, 2016

Evidence-based Health benefits of Fasting


10 Evidence-Based Health Benefits of Intermittent Fasting

Man Eating a Tiny Portion of FoodIntermittent fasting is an eating pattern where you cycle between periods of eating and fasting.
Numerous studies show that it can have powerful benefits for your body and brain.
Here are 10 evidence-based health benefits of intermittent fasting.

1. Intermittent Fasting Changes The Function of Cells, Genes and Hormones

When you don’t eat for a while, several things happen in your body.
For example, your body initiates important cellular repair processes and changes hormone levels to make stored body fat more accessible.
Here are some of the changes that occur in your body during fasting:
  • Insulin levels: Blood levels of insulin drop significantly, which facilitates fat burning (1).
  • Human growth hormone: The blood levels of growth hormone may increase as much as 5-fold (23). Higher levels of this hormone facilitate fat burning and muscle gain, and have numerous other benefits (45).
  • Cellular repair: The body induces important cellular repair processes, such as removing waste material from cells (6).
  • Gene expression: There are beneficial changes in several genes and molecules related to longevity and protection against disease (78).
Many of the benefits of intermittent fasting are related to these changes in hormones, gene expression and function of cells.
Bottom Line: When you fast, insulin levels drop and human growth hormone increases. Your cells also initiate important cellular repair processes and change which genes they express.

2. Intermittent Fasting Can Help You Lose Weight and Belly Fat

Many of those who try intermittent fasting are doing it in order to lose weight (9).
Generally speaking, intermittent fasting will make you eat fewer meals.
Unless if you compensate by eating much more during the other meals, you will end up taking in fewer calories.
Man Not Allowed to Eat Bell Pepper
Additionally, intermittent fasting enhances hormone function to facilitate weight loss.
Lower insulin levels, higher growth hormone levels and increased amounts of norepinephrine (noradrenaline) all increase the breakdown of body fat and facilitate its use for energy.
For this reason, short-term fasting actually increases your metabolic rate by 3.6-14%, helping you burn even more calories (1011).
In other words, intermittent fasting works on both sides of the calorie equation. It boosts your metabolic rate (increases calories out) and reduces the amount of food you eat (reduces calories in).
According to a 2014 review of the scientific literature, intermittent fasting can cause weight loss of 3-8% over 3-24 weeks (12). This is a huge amount.
The people also lost 4-7% of their waist circumference, which indicates that they lost lots of belly fat, the harmful fat in the abdominal cavity that causes disease.
One review study also showed that intermittent fasting caused less muscle loss than continuous calorie restriction (13).
All things considered, intermittent fasting can be an incredibly powerful weight loss tool. More details here: How Intermittent Fasting Can Help You Lose Weight.
Bottom Line: Intermittent fasting helps you eat fewer calories, while boosting metabolism slightly. It is a very effective tool to lose weight and belly fat.

3. Intermittent Fasting Can Reduce Insulin Resistance, Lowering Your Risk of Type 2 Diabetes

Blood Sugar Meter
Type 2 diabetes has become incredibly common in recent decades.
Its main feature is high blood sugar levels in the context of insulin resistance.
Anything that reduces insulin resistance should help lower blood sugar levels and protect against type 2 diabetes.
Interestingly, intermittent fasting has been shown to have major benefits for insulin resistance and lead to an impressive reduction in blood sugar levels (12).
In human studies on intermittent fasting, fasting blood sugar has been reduced by 3-6%, while fasting insulin has been reduced by 20-31% (12).
One study in diabetic rats also showed that intermittent fasting protected against kidney damage, one of the most severe complications of diabetes (13).
What this implies, is that intermittent fasting may be highly protective for people who are at risk of developing type 2 diabetes.
However, there may be some differences between genders. One study in womenshowed that blood sugar control actually worsened after a 22-day long intermittent fasting protocol (14).
Bottom Line: Intermittent fasting can reduce insulin resistance and lower blood sugar levels, at least in men.

4. Intermittent Fasting Can Reduce Oxidative Stress and Inflammation in The Body

Oxidative stress is one of the steps towards aging and many chronic diseases (14).
It involves unstable molecules called free radicals, which react with other important molecules (like protein and DNA) and damage them (15).
Several studies show that intermittent fasting may enhance the body’s resistance to oxidative stress (1617).
Additionally, studies show that intermittent fasting can help fight inflammation, another key driver of all sorts of common diseases (171819).
Bottom Line: Studies show that intermittent fasting can reduce oxidative damage and inflammation in the body. This should have benefits against aging and development of numerous diseases.

5. Intermittent Fasting May be Beneficial For Heart Health

Heart disease is currently the world’s biggest killer (20).
Brunette Holding a Clock and Waiting to Eat
It is known that various health markers (so-called “risk factors”) are associated with either an increased or decreased risk of heart disease.
Intermittent fasting has been shown to improve numerous different risk factors, including blood pressure, total and LDL cholesterol, blood triglycerides, inflammatory markers and blood sugar levels (12212223)
However, a lot of this is based on animal studies. The effects on heart health need to be studied a lot further in humans before recommendations can be made.
Bottom Line: Studies show that intermittent fasting can improve numerous risk factors for heart disease such as blood pressure, cholesterol levels, triglycerides and inflammatory markers.

6. Intermittent Fasting Induces Various Cellular Repair Processes

When we fast, the cells in the body initiate a cellular “waste removal” process calledautophagy (724).
This involves the cells breaking down and metabolizing broken and dysfunctional proteins that build up inside cells over time.
Increased autophagy may provide protection against several diseases, including cancer and Alzheimer’s disease (2526).
Bottom Line: Fasting triggers a metabolic pathway called autophagy, which removes waste material from cells.

7. Intermittent Fasting May Help Prevent Cancer

Happy Doctor
Cancer is a terrible disease, characterized by uncontrolled growth of cells.
Fasting has been shown to have several beneficial effects on metabolism that may lead to reduced risk of cancer.
Although human studies are needed, promising evidencefrom animal studies indicates that intermittent fasting may help prevent cancer (27282930).
There is also some evidence on human cancer patients, showing that fasting reduced various side effects of chemotherapy (31).
Bottom Line: Intermittent fasting has been shown to help prevent cancer in animal studies. One paper in humans showed that it can reduce side effects caused by chemotherapy.

8. Intermittent Fasting is Good For Your Brain

What is good for the body is often good for the brain as well.
Intermittent fasting improves various metabolic features known to be important forbrain health.
Hungry Woman With Empty Plate
This includes reduced oxidative stress, reduced inflammation and a reduction in blood sugar levels and insulin resistance.
Several studies in rats have shown that intermittent fasting may increase the growth of new nerve cells, which should have benefits for brain function (3233).
It also increases levels of a brain hormone called brain-derived neurotrophic factor (BDNF) (323435), a deficiency of which has been implicated in depression and various other brain problems (36).
Animal studies have also shown that intermittent fasting protects against brain damage due to strokes (37).
Bottom Line: Intermittent fasting may have important benefits for brain health. It may increase growth of new neurons and protect the brain from damage.

9. Intermittent Fasting May Help Prevent Alzheimer’s Disease

Illuminated Human Brain
Alzheimer’s disease is the world’s most common neurodegenerative disease.
There is no cure available for Alzheimer’s, so preventing it from showing up in the first place is critical.
A study in rats shows that intermittent fasting may delay the onset of Alzheimer’s disease or reduce its severity (38).
In a series of case reports, a lifestyle intervention that included daily short-term fasts was able to significantly improve Alzheimer’s symptoms in 9 out of 10 patients (39).
Animal studies also suggest that fasting may protect against other neurodegenerative diseases, including Parkinson’s and Huntington’s disease (4041).
However, more research in humans is needed.
Bottom Line: Studies in animals suggest that intermittent fasting may be protective against neurodegenerative diseases like Alzheimer’s disease.

10. Intermittent Fasting May Extend Your Lifespan, Helping You Live Longer

One of the most exciting applications of intermittent fasting may be its ability to extend lifespan.
Studies in rats have shown that intermittent fasting extends lifespan in a similar way as continuous calorie restriction (4243).
In some of these studies, the effects were quite dramatic. In one of them, rats that fasted every other day lived 83% longer than rats who weren’t fasted (44).
Although this is far from being proven in humans, intermittent fasting has become very popular among the anti-aging crowd.
Given the known benefits for metabolism and all sorts of health markers, it makes sense that intermittent fasting could help you live a longer and healthier life.
You can find more info about intermittent fasting on this page: Intermittent Fasting 101 – The Ultimate Beginner’s Guide.